Mark Cuban invests $250,000 in Packback on 'Shark Tank'

From left, Packback Books co-founders Kasey Gandham and Mike Shannon watch as they appear on "Shark Tank" at a viewing party at 1871. Packback received $250,000 from Mark Cuban on the show. (Armando L. Sanchez / for Blue Sky / Mar. 21, 2014)

Mark Cuban agreed to invest $250,000 in Chicago-based Packback in exchange for 20 percent equity in the company on Friday night’s episode of ABC's “Shark Tank.”

The Chicago-based company offers a pay-per-view way to read college textbooks. At a viewing party at 1871, guests stood and cheered as the Packback segment closed out the show where startup founders pitch their ideas to a panel of potential investors.

Kasey Gandham and Mike Shannon founded Packback in 2012 while undergraduates at Illinois State University.

Cuban was the only shark on the show who seemed to feel that any hurdles in negotiating with publishers could be overcome reasonably quickly. The segment was punctuated by jokes about how little time college students actually use their texts over the course of a semester — and a moment when Gandham mistakenly attempted to negotiate the billionaire investor’s terms down to $200,000 for the same percent of equity.

“I’m a sharp kid, I can do math,” Gandham said in the show wrapup. “But when you’re in the tank, it’s not that easy.”